WARNING - OLD ARCHIVES

This is an archived copy of the Xen.org mailing list, which we have
preserved to ensure that existing links to archives are not broken.
The live archive, which contains the latest emails, can be found at
http://lists.xen.org/

On Sun, Jul 10, 2011 at 04:14:49PM -0700, Paul E. McKenney wrote:
> On Sun, Jul 10, 2011 at 10:50:48PM +0100, julie Sullivan wrote:
> > > Very cool! Thank you very much for the testing --
.. snip..
> And here is what I am proposing sending upstream. I have your Tested-by,
Hey Paul,
I am hitting a similar bug.
Starting udev Kernel Device Manager...
Starting Configure read-only root support...
[ 79.942067] INFO: rcu_sched_state detected stalls on CPUs/tasks: { 0}
(detected by 2, t=60002 jiffies)
[ 79.942089] sending NMI to all CPUs:
when running a 3.0-rc6 under Xen as 32-bit guest (I don't see this issue
when running a 64-bit guest) and when I've more than two CPUs under the guest.
I've tried the patch below against 3.0-rc6 and it did not fix the issue.
I've also tried to use 3.0-rc3 as somewhere in thread one of the reporters
mentioned
that it worked for me - but that did not help me.
The config is a Fedora Core based. The stack traces of the four CPUs look
as follow:
CPU0:
Call Trace:
[<c04023a7>] hypercall_page+0x3a7 <--
[<c0405ed5>] xen_safe_halt+0x12
[<c040ea08>] default_idle+0x5a
[<c04081a6>] cpu_idle+0x8e
[<c07da9a9>] rest_init+0x5d
[<c0a86788>] start_kernel+0x34d
[<c0a861c4>] unknown_bootoption
[<c0a860ba>] i386_start_kernel+0xa9
[<c0a895ce>] xen_start_kernel+0x55d
[<c04090b1>] sys_rt_sigreturn+0xb
CPU1 and CPU2:
Call Trace:
[<c04023a7>] hypercall_page+0x3a7 <--
[<c0405ed5>] xen_safe_halt+0x12
[<c040ea08>] default_idle+0x5a
[<c04081a6>] cpu_idle+0x8e
[<c07e5419>] cpu_bringup_and_idle+0xd
CPU3:
Call Trace:
[<c042d0f2>] task_waking_fair+0x11 <--
[<c0439a45>] try_to_wake_up+0xb2
[<c0439b0c>] default_wake_function+0x10
[<c042d4db>] __wake_up_common+0x3b
[<c042ea69>] complete+0x3e
[<c0455e14>] wakeme_after_rcu+0x10
[<c048fd58>] __rcu_process_callbacks+0x172
[<c049080f>] rcu_process_callbacks+0x20
[<c044567d>] __do_softirq+0xa2
[<c04455db>] __do_softirq
[<c040a52d>] do_softirq+0x5a
The full config is http://darnok.org/xen/config-rcu-stall
The full bootup log is http://darnok.org/xen/log-rcu-stall
Any thoughts of what I ought to try? I don't know if there is some missing
functionality
in the RCU patches to work under Xen.... Any older version of Linux kernel
you would like me to try?
_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxxxxxxxx
http://lists.xensource.com/xen-devel